Java 8 Interview Questions and Answers

Java 8 Interview Questions

Here we have listed some of the standard Java 8 interview questions and answers that can help you gauge a candidate’s knowledge of the subject. You can also choose to ask other relevant questions that may stem from the answers given by the respondents if you decide to use these in face to face interviews.

Q1. What are the characteristics of a Lambda expression, and why is it used?

Answer: Lambda enables functional programming for writing better codes and also supports parallel processing. Optional type declaration, parentheses around parameter, curly braces, and return keyword, are some of the characteristics of a lambda expression.

Q2. What is Stream Pipelining in Java 8?

Answer: Streams in Java 8 enables function programming and use of Lambda expressions.   A stream pipeline includes intermediate operations that return an instance of a stream and a terminal operation which returns a final value and terminates the pipeline.

Q3. How are intermediate and terminal operations different?

Answer: Intermediate operations like filter, map, and flatmap returns a Stream and allows for further operations if required. Data can be processed with these operations only when there is a terminal operation like forEach, reduce, collect, sum, etc. These operations give a definite result, terminate the pipeline, and starts stream processing.

Q4. What is StringJoiner?

Answer: StringJoiner belongs to java.util package and is used to combine different strings into a single string with delimiters, and also with prefixes and suffixes. It uses two different constructors for this purpose. The constructors are Public StringJoiner(CharSequence delimiter) and Public StringJoiner(CharSequence delimiter, CharSequence prefix, CharSequence suffix).

Q5. What is Nashorn in Java?

Answer: Nashorn is a Javascript processing engine that has been brought in place of Rhino used in JDK 7 Java platform. It provides better runtime performance as it directly complies codes in memory and it passes bytecodes to Java virtual machine.

Parameters for Evaluating Java programmers

Some of the top parameters to evaluate a programmer’s responses to Java 8 questions and coding skills are listed below.

• Analyse the application of functional paradigm or OOPs
• View the number of lines in code and determine if it could have been shorter
• Examine the type of data structure used for problem-solving
• Check if the codes are easy to read, understand, and maintain
• Evaluate if the codes have the quality of extensibility
• Assess the quality of the Build Scripts
• Check the quality, readability and coverage of unit tests

Applications of MeritTrac Assessment Solutions

MeritTrac’s online assessment solutions let you administer tests online, invigilate remotely, get instant results, and make quick hiring decisions. These solutions are the result of years of scientific research and the adept use of modern technology to simplify global recruitment needs. MeritTrac is a leader in assessment solutions, and companies around the world use them to analyse the IT, managerial, and even behavioural competencies of people who seek employment with them.

Online assessment platforms can cut the result waiting time in half as the responses to test questions are auto-evaluated in minutes. This way, both recruiters and candidates can move on to the next level as per the test results. These tests also provide elaborate reports based on performance benchmarking which makes it easier for recruiters to understand the candidate’s strengths and weaknesses. 

During a performance appraisal, employees are usually left to wonder why they did not get the promotion or pay hike they hoped for. When Java 8 test report obtained through an online assessment platform is shared during feedback sessions employees can identify their strengths and weaknesses for themselves. It turns their discouragement into motivation and gives them the clarity to take the next step.